The present specification relates to correcting moving image wavering. In general, digital image capturing devices such as a digital camcorder, a digital camera, and the like, successively captures still images of 15 to 30 frames per second and displays the captured images via a display unit, e.g., a liquid crystal display (LCD) and the like, to show a user a moving image. Capturing moving images (i.e., video) by using the digital image capturing device inevitably accompanies an unpredictable motion, wobbling or waving (e.g., a panning and tilting phenomenon) by the user in contact with the digital image capturing device, so without a fixing means such as a tripod and the like, it is not easy to maintain a physically stable image capturing condition. Such unstableness in the physical image capturing state causes distortion of captured images. In addition, in case of a digital image capturing device using a complementary metal-oxide semiconductor (CMOS) module, e.g., a mobile terminal, image distortion may occur due to fine wobbling in rolling a shutter.
Such image distortion may become severe by the motion of the user moving along a path of action of a subject, wobbling of the digital image capturing device, and unstableness from wavering. As the number of frames captured per second is small, the interpolation distance according to the wobbling or wavering between frames is increased, so the unstableness of the captured image the user may feel is aggravated.
To correct moving image wavering of the digital image capturing device, optical wavering correction and nonoptical wavering correction can be performed. The optical wavering correction technique provides a device for basically overcoming wobbling or wavering with respect to an image inputted via the CMOS module to the digital image capturing device to prevent moving image wavering. For example, the optical wavering correction employs a gyro sensor, so that when a lens of the digital image capturing device moves in capturing moving images, the gyro sensor physically shifts the center of the lens in the opposite direction of the movement of the lens. However, for such optical wavering correction, the digital image capturing device should necessarily have an additional device to perform the corresponding function, resulting in an increase in the production costs and unit cost of products as well as a size of the products.
The nonoptical wavering correction technique is used to correct a captured image at a level of hardware or software in a chip state. For example, a motion vector of a movement (wavering or wobbling)-generated captured image is calculated and an offset of the captured image is adjusted by a corresponding amount to correct the image.